Many neurological diseases resulting from the loss of locomotor capacity are associated with pathologies of one or a combination of sensory pathways; proprioceptive, vestibular, or visual. The overall objective of the proposed research is to assess the contribution of sensory feedback for the initiation of muscular activity patterns appropriate to walking on sloped surfaces. By studying the electromyography of decerebrate walking cats, we can evaluate how sensory feedback from the proprioceptive system and the vestibular system influence terrain transitions. Initially, we will examine how head pitch and hindlimb orientation of an intact animal change during uphill and downhill walking in order to duplicate overground posture in future experiments. Next, we will manipulate treadmill slope and head pitch during a decerebrate walking preparation. Lastly, we will dismantle the vestibular system to evaluate the importance of this individual sensory system on the initiation of motor programs in response to changes in the environmental surface. Our preliminary data suggest that the neck proprioceptors and the vestibular system play a key role in the initiation of appropriate muscular activity patterns during walking. [unreadable] [unreadable]